RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 145347396 506 VSRTTDCVICMTAIDLRQHTS---DCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSLPP 561
Cdd:cd23117    1 ENGSVDCVICMSDIELPSTNSvrrDYMVTPCNHIFHTNCLERWMDIKLECPTCRRPLPP 59

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 145347396 506 VSRTTDCVICMTAIDLRQHTS---DCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSLPP 561
Cdd:cd23117    1 ENGSVDCVICMSDIELPSTNSvrrDYMVTPCNHIFHTNCLERWMDIKLECPTCRRPLPP 59

RING-finger-containing ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 145347396 511 DCVICMTAIDLRQHTsdcMVTPCEHFFHSGCLQRWM-DIKMECPTCRRSLPP 561
Cdd:COG5540  325 ECAICMSNFIKNDRL---RVLPCDHRFHVGCVDKWLlGYSNKCPVCRTAIPP 373

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 145347396 506 VSRTTDCVICMTAIDLRQHTS---DCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSLPP 561
Cdd:cd23117    1 ENGSVDCVICMSDIELPSTNSvrrDYMVTPCNHIFHTNCLERWMDIKLECPTCRRPLPP 59

RING-finger-containing ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 145347396 511 DCVICMTAIDLRQHTsdcMVTPCEHFFHSGCLQRWM-DIKMECPTCRRSLPP 561
Cdd:COG5540  325 ECAICMSNFIKNDRL---RVLPCDHRFHVGCVDKWLlGYSNKCPVCRTAIPP 373

H2 subclass of RING (RING-H2) fingers and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serves as a scaffold for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 145347396 512 CVICMTAIDLRQHtsdCMVTPCEHFFHSGCLQRWM-DIKMECPTCR 556
Cdd:cd16448    1 CVICLEEFEEGDV---VRLLPCGHVFHLACILRWLeSGNNTCPLCR 43

RING finger, H2 subclass, found in RING finger protein 115 (RNF115) and similar proteins; RNF115, also known as Rab7-interacting ring finger protein (Rabring 7), or zinc finger protein 364 (ZNF364), or breast cancer-associated gene 2 (BCA2), is an E3 ubiquitin-protein ligase that is an endogenous inhibitor of adenosine monophosphate-activated protein kinase (AMPK) activation and its inhibition increases the efficacy of metformin in breast cancer cells. It also functions as a co-factor in the restriction imposed by tetherin on HIV-1, and targets HIV-1 Gag for lysosomal degradation, impairing virus assembly and release, in a tetherin-independent manner. Moreover, RNF115 is a Rab7-binding protein that stimulates c-Myc degradation through mono-ubiquitination of MM-1. It also plays crucial roles as a Rab7 target protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis. Furthermore, RNF115 and the related protein, RNF126 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. RNF115 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 145347396 511 DCVICMTAIDLRQHTSDcmvTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16800    2 ECPVCKEDYTVGEQVRQ---LPCNHFFHSDCIVPWLELHDTCPVCRKSL 47

RING finger, H2 subclass, found in RING finger protein 145 (RNF145) and similar proteins; RNF145 is an uncharacterized RING finger protein encoded by the RNF145 gene, which is expressed in T lymphocytes, and its expression is altered in acute myelomonocytic and acute promyelocytic leukemias. Although its biological function remains unclear, RNF145 shows high sequence similarity with RNF139, an endoplasmic reticulum (ER)-resident multi-transmembrane protein that functions as a potent growth suppressor in mammalian cells, inducing G2/M arrest, decreased DNA synthesis and increased apoptosis. Like RNF139, RNF145 contains a C3H2C3-type RING-H2 finger with possible E3-ubiquitin ligase activity.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 145347396 512 CVICMtaidlrQHTSDCMVTPCEHFFHSGCLQRWMDIKMECPTC 555
Cdd:cd16684    5 CSICY------QDMKSAVITPCSHFFHAGCLKKWLYVQETCPLC 42

RING finger, H2 subclass, found in RING finger protein 44 (RNF44) and similar proteins; RNF44 is an uncharacterized RING finger protein that shows high sequence similarity with RNF38, which is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C2-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 145347396 507 SRTTDCVICMTAIDLRQHTSdcmVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16680    5 SEQTLCVVCFSDFESRQLLR---VLPCNHEFHTKCVDKWLKTNRTCPICR 51

RING finger, H2 subclass, found in DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3) and similar proteins; DZIP3, also known as RNA-binding ubiquitin ligase of 138 kDa (RUL138) or 2A-HUB protein, is an RNA-binding E3 ubiquitin-protein ligase that interacts with coactivator-associated arginine methyltransferase 1 (CARM1) and acts as a transcriptional coactivator of estrogen receptor (ER) alpha. It is also a histone H2A ubiquitin ligase that catalyzes monoubiquitination of H2A at lysine 119, functioning as a combinatorial component of the repression machinery required for repressing a specific chemokine gene expression program, critically modulating migratory responses to Toll-like receptors (TLR) activation. DZIP3 contains a C3H2C3-type RING-H2 finger at the C-terminus.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 145347396 510 TDCVICMTAIDLRQHTsdcMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16460    1 TPCVICHEAFSDGDRL---LVLPCAHKFHTQCIGPWLDGQQTCPTCR 44

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 145347396 511 DCVICMTAIDLRqhtsdCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd23130    2 VCPICLDDPEDE-----AITLPCLHQFCYTCILRWLQTSPTCPLCKTPV 45

RING finger, H2 subclass, found in RING finger protein 38 (RNF38) and similar proteins; RNF38 is a nuclear E3 ubiquitin protein ligase that is widely expressed throughout the human body, and is especially highly expressed in the heart, brain, placenta and the testis. It recognizes p53 as a substrate for ubiquitination, and thus plays a role in regulating p53. The overexpression of RNF38 increases p53 ubiquitination and alters p53 localization. It is also capable of autoubiquitination. RNF38 expression is negatively regulated by the serotonergic system. Induction of RNF38 may be involved in the anxiety-like behavior or non-cell autonomy in Oryzias latipes by the decline of serotonin (5-HT) levels. RNF38 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), a C3H2C3-type RING-H2 finger, as well as two potential nuclear localization signals.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 145347396 501 RFNRD--VSRTTDCVICMTAIDLRQHTSdcmVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16679   10 RFNPNnhQSEQTLCVVCMCDFESRQLLR---VLPCNHEFHAKCVDKWLKANRTCPICR 64

RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 145347396 511 DCVICMTAIDLRQhtsDCMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16454    1 TCAICLEEFKEGE---KVRVLPCNHLFHKDCIDPWLEQHNTCPLCR 43

RING finger, H2 subclass, found in RING finger protein 122 (RNF122) and similar proteins; RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. It interacts with calcium-modulating cyclophilin ligand (CAML), which is not a substrate, but a stabilizer of RNF122. RNF122 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 145347396 512 CVICMTAIDLRQHTSdcmVTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16676    3 CAVCLEDFKTKDELG---VLPCQHAFHRKCLVKWLEIRCVCPMCNKPI 47

RING finger, H2 subclass, found in RING finger protein 165 (RNF165) and similar proteins; RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. RNF165 contains two serine rich domains, a nuclear localization signal, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is responsible for the enhancement of BMP-Smad1/5/8 signaling in the spinal cord.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 145347396 512 CVICMTAIdlrQHTSDCMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16682   10 CTICLSML---EDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 51

RING finger, H2 subclass, found in RING finger protein 24 (RNF24) and similar proteins; RNF24 is an intrinsic membrane protein localized in the Golgi apparatus. It specifically interacts with the ankyrin-repeats domains (ARDs) of TRPC1, -3, -4, -5, -6, and -7, and affects TRPC intracellular trafficking without affecting their activity. RNF24 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 145347396 512 CVICMTAIDLRQHTSDCmvtPCEHFFHSGCLQRWMDIKMECPTC 555
Cdd:cd16675    3 CAVCLEEFKPKDELGIC---PCKHAFHRKCLIKWLEVRKVCPLC 43

RING finger, H2 subclass, found in RING finger proteins RNF24, RNF122, and similar proteins; This subfamily includes RNF24, RNF122, and similar proteins. RNF24 is an intrinsic membrane protein localized in the Golgi apparatus. It specifically interacts with the ankyrin-repeats domains (ARDs) of TRPC1, -3, -4, -5, -6, and -7, and affects TRPC intracellular trafficking without affecting their activity. RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. Both RNF24 and RNF122 contain an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 145347396 512 CVICMTAIDLRQHTSDCmvtPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16469    3 CAVCLEEFKLKEELGVC---PCGHAFHTKCLKKWLEVRNSCPICKSPV 47

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 145347396  512 CVICMtaiDLRQHTSdcMVTPCEHFFHSGCLQRWMDIKMECPTC 555
Cdd:pfam13923   2 CPICM---DMLKDPS--TTTPCGHVFCQDCILRALEASNECPLC 40

second RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the second RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 145347396 511 DCVICMTAIdlrqhtSDCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16514    3 ECSLCLRLL------YEPVTTPCGHTFCRACLERCLDHSPKCPLCRTSL 45

RING-H2 zinc finger domain; There are 8 cysteine/ histidine residues which are proposed to be the conserved residues involved in zinc binding. The protein, of which this domain is the conserved region, participates in diverse functions relevant to chromosome metabolism and cell cycle control.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 145347396  511 DCVICMTAID------LRQHTSDCMVT--PCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:pfam12678   2 TCAICRNPFMepcpecQAPGDDECPVVwgECGHAFHLHCISRWLKTNNTCPLCR 55

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 145347396 512 CVICMTAidlRQHTSdcmVTPCEHFFHSGCLQRWMDIKMECPTCRRSLPP 561
Cdd:cd16527    3 CSLCLEE---RRHPT---ATPCGHLFCWSCITEWCNEKPECPLCREPFQP 46

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 145347396 512 CVICMTAIdlrqhtSDCM-VTPCEHFFHSGCLQRWMDI-KMECPTCRRSL 559
Cdd:cd16503    5 CSICQDLL------HDCVsLQPCMHNFCAACYSDWMERsNTECPTCRATV 48

RING finger, H2 subclass, found in protein E3 ubiquitin-protein ligase Praja-1, Praja-2, and similar proteins; This family includes two highly similar E3 ubiquitin-protein ligases, Praja-1 and Praja-2. Praja-1, also known as RING finger protein 70, is a RING-H2 finger ubiquitin ligase encoded by gene PJA1, a novel human X chromosome gene abundantly expressed in the brain. It has been implicated in bone and liver development, as well as memory formation and X-linked mental retardation (MRX). Praja-1 interacts with and activates the ubiquitin-conjugating enzyme UbcH5B, and shows E2-dependent E3 ubiquitin ligase activity. It is a 3-deazaneplanocin A (DZNep)-induced ubiquitin ligase that directly ubiquitinates individual polycomb repressive complex 2 (PRC2) subunits in a cell free system, which leads to their proteasomal degradation. It also plays an important role in neuronal plasticity, which is the basis for learning and memory. Moreover, Praja-1 ubiquitinates embryonic liver fodrin (ELF) and Smad3, but not Smad4, in a transforming growth factor-beta (TGF-beta)-dependent manner. It controls ELF abundance through ubiquitin-mediated degradation, and further regulates TGF-beta signaling, which plays a key role in the suppression of gastric carcinoma. Praja-1 also regulates the transcription function of the homeodomain protein Dlx5 by controlling the stability of Dlxin-1, via a ubiquitin-dependent degradation pathway. Praja-2, also known as RING finger protein 131, NEURODAP1, or KIAA0438, is an E2-dependent E3 ubiquitin ligase that interacts with and activates the ubiquitin-conjugating enzyme UbcH5B. It functions as an A-kinase anchoring protein (AKAP)-like E3 ubiquitin ligase that plays a critical role in controlling cyclic AMP (cAMP)-dependent PKA activity and pro-survival signaling, and further promotes cell proliferation and growth. Praja-2 is also involved in protein sorting at the postsynaptic density region of axosomatic synapses and possibly plays a role in synaptic communication and plasticity. Together with the AMPK-related kinase SIK2 and the CDK5 activator CDK5R1/p35, it forms a SIK2-p35-PJA2 complex that plays an essential role for glucose homeostasis in pancreatic beta cell functional compensation. Praja-2 ubiquitylates and degrades Mob, a core component of NDR/LATS kinase and a positive regulator of the tumor-suppressor Hippo signaling. Both Praja-1 and Praja-2 contain a potential nuclear localization signal (NLS) and a C-terminal C3H2C3-type RING-H2 motif.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 145347396 512 CVICMTAIDLRQHTSDcmvTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16465    2 CPICCSEYVKDEIATE---LPCHHLFHKPCITAWLQKSGTCPVCRHVL 46

RING finger, H2 subclass, found in RING finger protein 103 (RNF103) and similar proteins; RNF103, also known as KF-1 or zinc finger protein 103 homolog (Zfp-103), is an endoplasmic reticulum (ER)-resident E3 ubiquitin-protein ligase that is widely expressed in many different organs, including brain, heart, kidney, spleen, and lung. It is involved in the ER-associated degradation (ERAD) pathway by interacting with components of the ERAD pathway, including Derlin-1 and VCP. RNF103 contains several hydrophobic regions at its N-terminal and middle regions, as well as a C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 145347396 510 TDCVICMTaiDLRQHTSDCmVTPCEHFFHSGCLQRWMD-IKMECPTCRR 557
Cdd:cd16473    5 EECAICLE--NYQNGDLLR-GLPCGHVFHQNCIDVWLErDNHCCPVCRW 50

RING finger, H2 subclass, found in RING finger protein 126 (RNF126) and similar proteins; RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). Moreover, RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. In addition, RNF126 and the related protein, RNF115 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. RNF126 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

                         10        20
                 ....*....|....*....|....*.
gi 145347396 532 PCEHFFHSGCLQRWMDIKMECPTCRR 557
Cdd:cd16801   19 PCNHLFHNDCIVPWLEQHDTCPVCRK 44

Modified RING finger, H2 subclass (C3H2C2D-type), found in zinc finger SWIM domain-containing protein 2 (ZSWIM2) and similar proteins; ZSWIM2, also known as MEKK1-related protein X (MEX) or ZZ-type zinc finger-containing protein 2, is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis through Fas, death receptor (DR) 3 and DR4 signaling. ZSWIM2 is self-ubiquitinated and targeted for degradation through the proteasome pathway. It acts as an E3 ubiquitin ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c, or UbcH6. ZSWIM2 contains four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain critical for its ubiquitination, and two modified RING-H2 fingers separated by a ZZ zinc finger domain, which was required for interaction with UbcH5a and its self-association. This model corresponds to the second RING-H2 finger, which is not a canonical C3H2C3-type, but a modified C3H2C2D-type.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 145347396 512 CVICMTAIDLRQHTSdcmVTPCEHFFHSGCLQRWMdiKMECPTC 555
Cdd:cd16486    2 CRICLKAFQLGQHVR---TLPCRHKFHRDCIDNWL--LHSRNSC 40

RING-CH finger, H2 subclass (C4HC3-type), found in transcriptional repressor NF-X1, NF-X1-type zinc finger protein NFXL1, and similar proteins; NF-X1, also known as nuclear transcription factor, X box-binding protein 1, is a novel cysteine-rich sequence-specific DNA-binding protein that interacts with the conserved X-box motif of the human major histocompatibility complex (MHC) class II genes via a repeated Cys-His domain. It functions as a cytokine-inducible transcriptional repressor that plays an important role in regulating the duration of an inflammatory response by limiting the period in which class II MHC molecules are induced by interferon gamma (IFN- gamma). NFXL1, also known as NF-X1-type zinc finger protein NFXL1 or ovarian zinc finger protein (OZFP), is encoded by a novel human cytoplasm-distribution zinc finger protein (CDZFP) gene. This subfamily also includes NF-X1 homologs from insects, plants, and fungi. Drosophila melanogaster shuttle craft (STC) is a DNA- or RNA-binding protein required for proper axon guidance in the central nervous system. It functions as a putative transcription factor and plays an essential role in the completion of embryonic development. In contrast to NF-X1, STC contains an RD domain. The Arabidopsis genome encodes two NF-X1 homologs, AtNFXL1 and AtNFXL2, both of which function as regulators of salt stress responses. The AtNFXL1 protein is a nuclear factor that positively affects adaptation to salt stress. It also functions as a negative regulator of the type A trichothecene phytotoxin-induced defense response. AtNFXL2 controls abscisic acid (ABA) levels and suppresses ABA responses. It may also prevent unnecessary and costly stress adaptation under favorable conditions. FKBP12-associated protein 1 (FAP1) is a dosage suppressor of rapamycin toxicity in budding yeast. It is localized in the cytoplasm, but upon rapamycin treatment translocates to the nucleus. FAP1 interacts with FKBP12 in a rapamycin-sensitive manner. It is a proline-rich protein containing a novel cysteine-rich DNA-binding motif. Unique structural features of the NFX1 and NFXL proteins are the Cys-rich region and a specific RING-CH finger motif with an unusual arrangement of zinc-coordinating residues. The Cys-rich region is required for binding to specific promoter elements. It frequently comprises more than 500 amino acids and harbors several NFX1-type zinc finger domains, characterized by the pattern C-X(1-6)-H-X-C-X3-C(H/C)-X(3-4)-(H/C)-X(1-10)-C. The RING-CH finger, also known as vRING or RINGv, may have E3 ligase activity. It is characterized by a C4HC3-type Zn ligand signature and additional conserved amino acids, rather than the C3H2C3-type cysteines and histidines arrangement in canonical RING-H2 finger. In addition to the Cys-rich region and RING-CH finger, NFX1 contains a PAM2 motif in the N-terminus and a R3H domain in the C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 145347396 511 DCVICMTAIDLRQHTSDCMVtpCEHFFHSGCLQRWMDIKME-------------CPTCR 556
Cdd:cd16492    2 ECMICTENVGRNQSIWSCSR--CYRVFHLSCIKKWAKNSEEkaeqvkndddswrCPGCQ 58

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 145347396 512 CVICMTAIdlrqhtSDCM-VTPCEHFFHSGCLQRWMDI-KMECPTCRRSLP 560
Cdd:cd16531    4 CPICLGII------KNTMtVKECLHRFCAECIEKALRLgNKECPTCRKHLP 48

zinc-RING finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 145347396  512 CVICMTaidLRQHTSDCMVTPCEHFFHSGCLQRwMDIKMECPTCRR 557
Cdd:pfam14634   2 CNKCFK---ELSKTRPFYLTSCGHIFCEECLTR-LLQERQCPICKK 43

RING finger, H2 subclass, found in RING finger protein 25 (RNF25) and similar proteins; RNF25, also known as AO7, is a putative E3 ubiquitin-protein ligase that was initially identified as an interacting protein of the E2 ubiquitin-conjugating enzyme, Ubc5B. It is ubiquitously expressed in various tissues and predominantly localized in the nucleus. RNF25 activates the nuclear factor (NF)-kappaB-dependent gene expression upon stimulation with Interleukin-1 beta (IL-1beta), or tumor necrosis factor (TNF), or overexpression of NF-kappaB-inducing kinase. It interacts with the p65 transactivation domain (TAD) and modulates its transcriptional activity. RNF25 contains an N-terminal RWD domain, a C3H2C3-type RING-H2 finger, and a C-terminal Pro-rich region. Both the RING-H2 finger and the C-terminal regions of RNF25 are necessary for transcriptional activation.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 145347396 512 CVICMTAIdlrQHTSDCMVTPCEHFFHSGCLQRW-----MDIKME--------------------CPTCRRSL 559
Cdd:cd16470    5 CVICLYGF---QEGDAFTKTPCYHYFHSHCLARYiqhmeENLKEEqeeqeerpraqteqeqfqvlCPVCREPL 74

RING finger, H2 subclass, found in RING finger protein 130 (RNF130) and similar proteins; RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL). It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property, and controls the development of T cell clonal anergy by ubiquitination. RNF130 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 145347396 515 CMTAIDLRQHTSDCMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16803    3 CAVCIEGYKQNDVVRILPCKHVFHKSCVDPWLNEHCTCPMCK 44

RING finger, HC subclass, found in postreplication repair protein RAD18 and similar proteins; RAD18, also known as HR18 or RING finger protein 73 (RNF73), is an E3 ubiquitin-protein ligase involved in post replication repair of UV-damaged DNA via its recruitment to stalled replication forks. It associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on K164. It also interacts with another E2 ubiquitin conjugating enzyme RAD6 to form a complex that monoubiquitinates proliferating cell nuclear antigen at stalled replication forks in DNA translesion synthesis. Moreover, Rad18 is a key factor in double-strand break DNA damage response (DDR) pathways via its association with K63-linked polyubiquitylated chromatin proteins. It can function as a mediator for DNA damage response signals to activate the G2/M checkpoint in order to maintain genome integrity and cell survival after ionizing radiation (IR) exposure. RAD18 contains a C3HC4-type RING-HC finger, a ubiquitin-binding zinc finger domain (UBZ), a SAP (SAF-A/B, Acinus and PIAS) domain, and a RAD6-binding domain (R6BD).

                         10        20
                 ....*....|....*....|....*...
gi 145347396 529 MVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16529   19 MITQCSHNYCSLCIRRFLSYKTQCPTCR 46

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 145347396 512 CVICMTAIDLRQhtsdcMVTPCEHFFHSGCLQRWMDIKMECPTCRR 557
Cdd:cd16506    3 CPICLDEIQNKK-----TLEKCKHSFCEDCIDRALQVKPVCPVCGV 43

RING finger, H2 subclass, found in rice E3 ubiquitin-protein ligase EL5 and similar proteins; EL5, also known as protein ELICITOR 5, is an E3 ubiquitin-protein ligase containing an N-terminal transmembrane domain and a C3H2C3-type RING-H2 finger that is a binding site for ubiquitin-conjugating enzyme (E2). It can be rapidly induced by N-acetylchitooligosaccharide elicitor. EL5 catalyzes polyubiquitination via the Lys48 residue of ubiquitin, and thus plays a crucial role as a membrane-anchored E3 in the maintenance of cell viability after the initiation of root primordial formation in rice. It also acts as an anti-cell death enzyme that might be responsible for mediating the degradation of cytotoxic proteins produced in root cells after the actions of phytohormones. Moreover, EL5 interacts with UBC5b, a rice ubiquitin carrier protein, through its RING-H2 finger. EL5 is an unstable protein, and its degradation is regulated by the C3H2C3-type RING-H2 finger in a proteasome-independent manner.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 145347396 511 DCVICMTaiDLRQHTSDCMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16461    1 ECAICLS--DYENGEELRRLPECKHAFHKECIDEWLKSNSTCPLCR 44

The RING-variant domain is a C4HC3 zinc-finger like motif found in a number of cellular and viral proteins; Some of these proteins have been shown both in vivo and in vitro to have ubiquitin E3 ligase activity. The RING-variant domain is reminiscent of both the RING and the PHD domains and may represent an evolutionary intermediate. To describe this domain the term PHD/LAP domain has been used in the past. Extended description: The RING-variant (RINGv) domain contains a C4HC3 zinc-finger-like motif similar to the PHD domain, while some of the spacing between the Cys/His residues follow a pattern somewhat closer to that found in the RING domain. The RINGv domain, similar to the RING, PHD and LIM domains, is thought to bind two zinc ions co-ordinated by the highly conserved Cys and His residues. RING variant domain: C-x (2) -C-x(10-45)-C-x (1) -C-x (7) -H-x(2)-C-x(11-25)-C-x(2)-C As opposed to a PHD: C-x(1-2) -C-x (7-13)-C-x(2-4)-C-x(4-5)-H-x(2)-C-x(10-21)-C-x(2)-C Classical RING domain: C-x (2) -C-x (9-39)-C-x(1-3)-H-x(2-3)-C-x(2)-C-x(4-48) -C-x(2)-C

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 145347396   511 DCVICMTAIDlrqhTSDCMVTPCE-----HFFHSGCLQRWMDIK--MECPTCR 556
Cdd:smart00744   1 ICRICHDEGD----EGDPLVSPCRckgslKYVHQECLERWINESgnKTCEICK 49

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6 and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. Moreover, RNF6 regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 also binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. RNF6 also acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF6 contains an N-terminal coiled-coil domain, a Lys-X-X-Leu/Ile-X-X-Leu/Ile (KIL) motif, and a C-terminal C3H2C3-type RING-H2 finger which is responsible for its ubiquitin ligase activity. The KIL motif is present in a subset of RING-H2 proteins from organisms as evolutionarily diverse as human, mouse, chicken, Drosophila, Caenorhabditis elegans, and Arabidopsis thaliana.

                         10        20
                 ....*....|....*....|....*.
gi 145347396 532 PCEHFFHSGCLQRWMDIKMECPTCRR 557
Cdd:cd16673   20 PCAHEFHIHCIDRWLSENSTCPICRQ 45

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, and similar proteins. RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It also interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 145347396 511 DCVICMTAI----DLRQhtsdcmvTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16474    2 KCTICLSDFeegeDVRR-------LPCMHLFHQECVDQWLSTNKRCPICR 44

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

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                 ....*....|....*....|....*....|....*....|....*...
gi 145347396 511 DCVICMTAIDLRQHtsdcmVTPCEHFFHSGCLQRWMDIKME--CPTCR 556
Cdd:cd16749    2 ECPVCFEKLDVTAK-----VLPCQHTFCKPCLQRIFKARKElrCPECR 44

RING finger, HC subclass, found in RING finger protein 8 (RNF8) and similar proteins; RNF8 is a telomere-associated E3 ubiquitin-protein ligase that plays an important role in DNA double-strand break (DSB) repair via histone ubiquitination. It is localized in the nucleus and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3), but not with other E2s (UbcH5, UbcH7, UbcH10, hCdc34, and hBendless). It recruits UBC13 for lysine 63-based self polyubiquitylation. Its deficiency causes neuronal pathology and cognitive decline, and its loss results in neuron degeneration. RNF8, together with RNF168, catalyzes a series of ubiquitylation events on substrates such as H2A and H2AX, with the H2AK13/15 ubiquitylation being particularly important for recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of DSBs. RNF8 mediates the ubiquitination of gammaH2AX, and recruits 53BP1 and BRCA1 to DNA damage sites which promotes DNA damage response (DDR) and inhibits chromosomal instability. Moreover, RNF8 interacts with retinoid X receptor alpha (RXR alpha) and enhances its transcription-stimulating activity. It also regulates the rate of exit from mitosis and cytokinesis. RNF8 contains an N-terminal forkhead-associated (FHA) domain and a C-terminal C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 145347396 512 CVICmtaidlRQHTSDCMVTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd16535    4 CSIC------SELFIEAVTLNCSHSFCSYCITEWMKRKKECPICRKPI 45

Component of SCF ubiquitin ligase and anaphase-promoting complex [Posttranslational modification, protein turnover, chaperones / Cell division and chromosome partitioning];

                         10        20
                 ....*....|....*....|....*
gi 145347396 533 CEHFFHSGCLQRWMDIKMECPTCRR 557
Cdd:COG5194   54 CNHAFHDHCIYRWLDTKGVCPLDRQ 78

RING finger, H2 subclass, found in Arabidopsis thaliana protein ABA INSENSITIVE RING PROTEIN 1 (AIRP1) and similar proteins; This subfamily includes Arabidopsis thaliana AIRP1 and RING-H2 finger B1a (RHB1A). AIRP1, also known as RING-type E3 ubiquitin transferase AIRP1, possesses E3 ubiquitin-protein ligase activity in vitro when associated with the E2 enzyme UBC8. It plays combinatory roles with AIRP2 in the positive regulation of the abscisic acid-mediated drought stress response. RHB1A is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 145347396 512 CVICmtaidLRQHTSDC--MVTPCEHFFHSGCLQRWMDIKMECPTCRRSL 559
Cdd:cd23116    5 CPTC-----LEGYTEENpkLLTKCGHHFHLACIYEWMERSERCPVCDKEM 49

RING finger, H2 subclass, found in Arabidopsis thaliana MED25-binding RING-H2 protein (MBR) and similar proteins; This subfamily includes MBR1 and MBR2 (also called HAL3-interacting protein 1 or AtHIP1). They are E3 ubiquitin-protein ligases that function as regulators of MED25 stability by targeting MED25 for degradation in a RING-H2-dependent manner. Proteasome-dependent degradation of MED25 seems to activate its function as a positive regulator of FLOWERING LOCUS T (FT) and is important to induce the expression of FT, and consequently to promote flowering. MBR2 may also function downstream of HAL3 and be required for HAL3-regulated plant growth. Activation of MBR2 by HAL3 may lead to the degradation of cell cycle suppressors, resulting in enhancement of cell division and plant growth. Both MBR1 and MBR2 contain a C3H2C3-type RING-H2 finger.

                         10        20
                 ....*....|....*....|....
gi 145347396 533 CEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd23113   23 CGHEYHSDCIKQWLVQKNLCPICK 46

RING finger, H2 subclass, found in zinc/RING finger protein 3 (ZNRF3) and similar proteins; ZNRF3, also known as RING finger protein 203 (RNF203), is a homolog of Ring finger protein 43 (RNF43). It is a transmembrane E3 ubiquitin-protein ligase that is associated with the Wnt receptor complex, and negatively regulates Wnt signaling by promoting the turnover of frizzled and lipoprotein receptor-related protein LRP6 in an R-spondin-sensitive manner. It inhibits gastric cancer cell growth and promotes cell apoptosis by affecting the Wnt/beta-catenin/TCF signaling pathway. ZNRF3 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region.

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                 ....*....|....*....|....*....|....*....|....*....
gi 145347396 511 DCVICMTA-IDlrqhTSDCMVTPCEHFFHSGCLQRWMDIKMECPTCRRS 558
Cdd:cd16799    1 DCAICLEKyID----GEELRVIPCTHRFHKKCVDPWLLQHHTCPHCRHN 45

RING finger, H2 subclass, found in Saccharomyces cerevisiae vacuolar membrane protein PEP3 (Pep3p) and similar proteins; Pep3p, also known as carboxypeptidase Y-deficient protein 3, vacuolar morphogenesis protein 8, vacuolar protein sorting-associated protein 18 (Vps18p), or vacuolar protein-targeting protein 18, is a vacuolar membrane protein that affects late Golgi functions required for vacuolar protein sorting and efficient alpha-factor prohormone maturation. It is required for vacuolar biogenesis and for trafficking of hydrolase precursors to the vacuole. The disruption of PEP3 may cause hypersensitivity to heat shock and ethanol stresses, probably due to disappearance of normal vacuoles. As a component of the homotypic fusion and vacuole protein sorting (HOPS) and class C core vacuole/endosome tethering (CORVET) complexes, its overexpression shortens lag phase but does not alter growth rate in Saccharomyces cerevisiae exposed to acetic acid stress. Moreover, Pep3p forms the Class C Vps protein complex (C-Vps complex) with Pep5p (also known as Vps11), Vps16, and Vps33, and is necessary for trafficking of hydrolase precursors to the vacuole by promoting vesicular docking reactions with SNARE proteins. Pep3p contains a C3H2C3-type RING-H2 finger at the C-terminus.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 145347396 512 CVICMTAIdlrqHTSDCMVTPCEHFFHSGCLQRWM---DIKMECPTC 555
Cdd:cd16462    3 CAVCGRPL----LTRQFYVFPCQHAFHADCLIEEVlddLIASECPLC 45

RING-CH finger, H2 subclass (C4HC3-type), found in E3 ubiquitin-protein ligase listerin and similar proteins; Listerin, also known as RING finger protein 160 or zinc finger protein 294, is the mammalian homolog of yeast Ltn1. It is widely expressed in all tissues, but motor and sensory neurons and neuronal processes in the brainstem and spinal cord are primarily affected in the mutant. Listerin is required for embryonic development and plays an important role in neurodegeneration. It also functions as a critical E3 ligase involving quality control of nonstop proteins. It mediates ubiquitylation of aberrant proteins that become stalled on ribosomes during translation. Ltn1 works with several cofactors to form a large ribosomal subunit-associated quality control complex (RQC), which mediates the ubiquitylation and extraction of ribosome-stalled nascent polypeptide chains for proteasomal degradation. It appears to first associate with nascent chain-stalled 60S subunits together with two proteins of unknown function, Tae2 and Rqc1. Listerin contains a long stretch of HEAT (Huntingtin, Elongation factor 3, PR65/A subunit of protein phosphatase 2A, and TOR) or ARM (Armadillo) repeats in the N terminus and middle region, and a catalytic RING-CH finger, also known as vRING or RINGv, with an unusual arrangement of zinc-coordinating residues in the C-terminus . Its cysteines and histidines are arranged in the sequence as C4HC3-type, rather than the C3H2C3-type in canonical RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*....|..
gi 145347396 510 TDCVICMTAIDLRQHT---SDCMVtpCEHFFHSGCLQRWMDI--KMECPTCR 556
Cdd:cd16491    1 EECPICYSVIHGSNHSlpkLKCKT--CKNKFHSACLYKWFRSsnKSTCPLCR 50

RING finger, H2 subclass, found in RING finger proteins RNF43, ZNRF3, and similar proteins; RNF43 and ZNRF3 (also known as RNF203) are transmembrane E3 ubiquitin-protein ligases that belong to the PA-TM-RING ubiquitin ligase family, characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region. Both RNF43 and RNF203 function as tumor suppressors involved in the regulation of Wnt/beta-catenin signaling. They negatively regulate Wnt signaling by interacting with complexes of frizzled (FZD) receptors and low-density lipoprotein receptor-related protein (LRP) 5/6, which leads to ubiquitination of FZD and endocytosis of the Wnt receptor. Dishevelled (DVL), a positive Wnt regulator, is required for ZNRF3/RNF43-mediated ubiquitination and degradation of FZD. They also associate with R-spondin 1 (RSPO1). This interaction may block FZD ubiquitination and enhances Wnt signaling.

                         10        20        30        40
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gi 145347396 511 DCVICMTAIDLRQhtsDCMVTPCEHFFHSGCLQRWMDIKMECPTCR 556
Cdd:cd16666    1 VCAICLEEYEEGQ---ELRVLPCQHEFHRKCVDPWLLQNHTCPLCL 43

RING finger, HC subclass, found in RING finger protein RNF224 and similar proteins; RNF224 is uncharacterized C3HC4-type RING-HC finger-containing proteins. It may function as an E3 ubiquitin-protein ligase.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 145347396 510 TDCVICMTAIDLRQHTSDCMVtpCEHFFHSGCL---------QRWmdikMECPTCRRSLP 560
Cdd:cd16565    1 LDCIICYSAYDLSTRLPRRLY--CGHTFCQACLkrldtvineQRW----IPCPQCRQNTP 54

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in zinc/RING finger protein 2 (ZNRF2) and similar proteins; ZNRF2, also known as protein Ells2 or RING finger protein 202 (RNF202), is an E3 ubiquitin-protein ligase that is highly expressed in the nervous system during development and is present in presynaptic plasma membranes. It is N-myrisotoylated and is also located in the endosome-lysosome compartment in fibroblasts. It contains an N-terminal MAGE domain, and a special C-terminal domain that combines a zinc finger and a modified C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of RING-H2 finger. Only the RING finger of the zinc finger-RING finger motif is required for its E3 ubiquitin ligase activity. Together with its sister protein ZNRF1, ZNRF2 regulates the ubiquitous Na+/K+ pump (Na+/K+ATPase).

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gi 145347396 502 FNRDV--SRTTDCVICMTAIdlrQHTSDCMVTPCEHFFHSGCLQRWMDIKMECP 553
Cdd:cd16695    1 YNEDVlsKDAGECAICLEEL---QQGDTIARLPCLCIYHKGCIDEWFEVNRSCP 51